The Funny Bone: it’s no laughing matter

Elbows are ugly. Let’s face it, they’re not the prettiest bones in your body. They’re pushy and pugnacious – delicately curtained off by a demure fall of wrinkly skin when not in use. And for good reason. An elbow has its own power and is ready to be put into aggressive action at a moment’s notice. And while crucial to most sporting success, they have never liked tennis.

One is often accused of elbowing one’s way into something – or out for that matter. They are always in on any determined action. To throw a good punch, you need a strong elbow. And of course, when required to do some hard work, you are often encouraged to ‘put your elbow into it’. And without their sturdy support at a table most of us would be lying on the floor.

Funny Peculiar

But for all their bravado, elbows have a curious vulnerability – and that is, when struck on a certain sensitive spot, you could actually end up lying on the floor. We call it rather euphemistically, the ‘funny bone’ because if hurt in this way, we can feel giddy and peculiar, caught between laughing, crying and even fainting. The pain can be extraordinary, unlike anything you might feel anywhere else in the body from a slight bump or knock. For a few excruciating seconds you might feel as though every nerve in your body has slid down your arm and found vital import in your elbow.

But the fact of the matter is that although we refer to the elbow as the funny bone, it is not the bone itself that causes the problem. The funny bone is not a bone at all, but actually the ulnar nerve that runs from the neck all the way to the hand, where it serves several muscles in the hand and forearm and ends in two branches that innervate the little finger and half of the ring finger, and which helps to stimulate movement in the hand and wrist.

As it passes the elbow, this nerve runs through a channel called the cubital tunnel. This is a tunnel of tissue on the inside of the elbow under a bony portion of the humerus (your upper arm bone) called the medial epicondyle. At this point, the ulnar nerve’s protection is reduced to a thin sheath of skin and fat, making it vulnerable to bumps. When you hit your funny bone, you’re actually hitting the nerve against the bone and compressing it. This causes a dizzy numbness and tingling that runs down the arm to your hand.

So why do we call what is essentially a nerve, the ‘funny bone’?

Some say it’s because the nerve that causes the giddy sensation runs along the humerus, and therefore there’s a play on the word ‘humorous’. However, it may more likely be due to the very peculiar feeling you get after knocking it. Because hitting the funny bone can temporarily stop the nerve’s connection to the brain, resulting in that dizzy numbness or even faintness. We sometimes tend to laugh afterwards because we feel somewhat foolish regarding our rather dramatic reactions to a bump on the elbow. And while hitting your funny bone is something you can usually laugh about once the pain subsides, in some instances the pain and discomfort is ongoing when serious conditions arise from an unwell elbow.

Conditions of the elbow

Cubital tunnel syndrome

  • This condition can develop when the ulnar nerve becomes regularly obstructed and over time, progressive irritation of the nerve causes the numbness to become permanent. Causation is usually from regular movements where your elbow is bent, like spending large parts of the day making phone calls and holding your phone to your ear, or through various repetitive movements in sports or factory work.
  • Muscle weakness in the forearm and hand can also set in, and the little finger and ring finger can curl up in a position called the “ulnar claw.” The condition can usually be helped with elbow splinting, hand therapy or, in extreme cases, surgery that provides more space for the nerve and reduces the amount of pressure on it.

Tennis Elbow

  • This caused by the inflammation of the lateral epicondylitis, one of the most common elbow problems, usually caused by a sudden injury or by repetitive use of the arm. It is actually a tendinitis of the muscle called the extensor carpi radialis brevis which attaches to the lateral epicondyle of the humerus. There! And if you manage to say all this without developing tennis tongue you have the up on the elbow.
  • The micro tears in the tendon lead to a hyper-vascular phenomenon resulting in pain. The pain is usually worse with strong gripping with the elbow in an extended position, as in a tennis back hand stroke, but this problem can occur in golf and other sports as well as with repetitive use of tools.
  • Rest, anti-inflammatories, physical therapy, a brace, cortisone injections are all treatments before surgery is considered. Procedures as simple as percutaneous release of the tendon off of the bone, or more recently arthroscopic procedures or other procedures involving the joint and resection of a ligament, have been suggested as successful remedies.

Golfer’s Elbow

  • This follows in a similar way to tennis elbow. Medial epicondylitis is inflammation of the tendon attachment of the flexor pronator muscles in the forearm. Usually this begins as microscopic tears in the tissue which leads to an inflammatory or hyper-vascular process.
  • This occurs when stiff, underused tendons are suddenly overused or this may occur from an acute injury. The treatment is also similar to that taken for tennis elbow as outlined above.

Osteoarthritis

  • The elbow is one of the joints least affected by this condition because of its well-matched joint surfaces and strong stabilising ligaments. As a result, the elbow joint can tolerate large forces across it without becoming unstable. However, a fracture or dislocation increases the risk of arthritis for the elbow, especially after surgery, loss of joint cartilage, and injury to ligaments causing unnatural joint stress.
  • Again, repetitive actions in sports or work situations can cause the kind of wear and tear that can lead to osteoarthritis. Individuals involved in heavy work or sports activities should maintain muscular strength around the elbow. Proper conditioning and technique should always be used. The best way to prevent elbow arthritis is to avoid injury to the joint. The most common symptoms of elbow arthritis are pain and loss of range of motion.
  • Both of these symptoms may not occur at the same time. Patients usually report a ‘grating’ or ‘locking’ sensation in the elbow. The latter is due to loss of the normal smooth joint surface, caused by cartilage damage or wear. The ‘locking’ is caused by loose pieces of cartilage or bone that dislodge from the joint and become trapped between the moving joint surfaces, blocking motion. While this is a cartilage condition, treatment follows the above-mentioned options, while surgery may offer varied, but sometimes limited intervention.

Take care of your elbows, even though they can be awkward and often in the way, knocking over things. They do an enormous amount of work for you. Love your bones!

NOFSA (National Osteoporosis Foundation South Africa)

NOFSA is the only non-profit, voluntary health organisation dedicated to promoting lifelong bone health. We focus on reducing the widespread prevalence of osteoporosis while working to find a cure for the disease, and by supporting research and developing programmes of education and advocacy.

Find out more about our work at: www.osteoporosis.org.za